Cancer survivorship research: challenge and opportunity.

With continued advances in strategies to detect cancer early and treat it effectively along with the aging of the population, the number of individuals living years beyond a cancer diagnosis can be expected to continue to increase. This paper reviews current prevalence data for cancer survivors; discusses definitional issues; examines cancer survivorship as a scientific research area; provides an overview of medical and psychosocial sequelae of cancer diagnosis and treatment experienced by survivors, gaps in knowledge and emerging research priorities; explores the role of weight, nutrition and physical activity as key variables carrying the potential to affect physiologic or psychosocial sequelae of cancer and its treatment; and discusses the evolving paradigm of cancer survivorship research. A large and growing community of cancer survivors is one of the major achievements of cancer research over the past three decades. Both length and quality of survival are important end points. Many cancer survivors are at risk for and develop physiologic and psychosocial late and long-term effects of cancer treatment that may lead to premature mortality and morbidity. Interventions--therapeutic and lifestyle--carry the potential to treat or ameliorate these late effects and must be developed, examined and disseminated if found effective. Diet, weight and physical activity interventions hold considerable promise for ameliorating multiple adverse sequelae of cancer and its treatment and should be investigated in larger populations of cancer survivors, those who are long-term survivors, those with understudied cancer sites and ethnocultural minority or medically underserved groups.